Arrangement of the sensor of temperature of N1 cooling liquid (4-cylinder models)

The sensor of temperature of N1 cooling liquid (it is specified by an arrow) is located in a back part of a radiator.

Arrangement of the sensor of temperature of N1 cooling liquid (6-cylinder models)

In 6-cylinder models the sensor of temperature of cooling liquid (it is specified by an arrow) is located on a thermostat casing.

The main relay of the engine and the relay of the cooling N1 fan – the Avalon model

And – the main relay of the engine In – the relay of the cooling fan

The block of the relay of the cooling fan – the Avalon model

Check

PERFORMANCE ORDER

1. If the cooling fan is not switched off when the engine cooled down, disconnect a wire from the temperature sensor of the fan and close contacts of a wire a crossing point. If the fan stops, replace the sensor.

2. Check the N1 fan sensor by means of an ohmmeter. When the engine cold, the chain of the sensor has to be closed. When the engine is warmed, the chain of the sensor has to be opened.

3. Check the N2 sensor similarly. The chain is opened if temperature is below 84 °C and the chain is closed if temperature more than 90 °C. If necessary replace the sensor.

4. If the fan motor is faulty, for a start, check the fan fuse located under a cowl in the block of the relay and fuses. Disconnect a wire from the motor of the fan and connect contacts of the fan by means of adapters to accumulator plugs. If the fan still does not work, replace the motor.

5. If sensors are serviceable and the motor underwent testing, means it is necessary to check the fan relay, conducting and an electronic control unit.

Check of the relay

PERFORMANCE ORDER

1. The block of the relay is located on the left side in a motive compartment. If the car is equipped with air conditioning system, then in the block of the relay there is a N2 relay of the second fan, and in some models there is a N3 relay (see rice. The block of the relay of the cooling fan – the Avalon model).

2. Remove the N1 relay and check it by means of an ohmmeter. The chain has to be closed between contacts 1 and 2 (85 and 86 on the relay of Bosch) and between contacts 3 and 4 (30 and 87a 86 on the relay of Bosch). When on contacts 1 and 2 accumulator tension moves, between contacts the 3 and 4 chain has to be opened.

3. If the relay functions regularly, remove the main relay of the engine and check it. The chain is closed between contacts 3 and 5 and contacts 2 and 4. the chain is opened between contacts 1 and 2. When tension on contacts 3 and 5, a chain 1–2 moves it is closed, and the chain 2–4 is opened. If all relays work regularly, and the fan still does not function, address the expert.

Replacement

PERFORMANCE ORDER

1. Disconnect a wire of the minus plug of the accumulator.

2. Disconnect a wire from the fan motor. Disconnect the wires fixed on a fan casing.

3. Unscrew bolts (are specified by shooters) and get a fan casing from office of the engine.

4. Turn off a nut of the fan and remove the fan from the electric motor.